A liquid crystal display device which uses liquid crystals as a light modulation element includes a backlight portion which illuminates a liquid crystal panel from a rear surface, and achieves display of a desired image by controlling transmissivity of light emitted from the backlight portion, by liquid crystals. In recent years, technology has become known which uses light sources, such as light emitting diodes, as backlight portions, and controls the light emission luminance of respective light sources in accordance with the image signals of divided regions of the liquid crystal panel which are illuminated by the respective light sources.
In the case where the light emission luminance of the light sources are controlled, in order to maintain the brightness of the image which is displayed on the liquid crystal panel at a level corresponding to the input image signal, it is necessary to correct the transmissivity of the liquid crystals in accordance with the luminance of the backlight portion which is incident on the liquid crystal panel. Therefore, in order to accurately determine the luminance of the backlight portion which is incident on the liquid crystal panel, in the technology described in Patent Document 1, for example, additional luminance calculation points are provided between mutually adjacent divided regions, in addition to basic luminance calculation points of respective divided regions which are provided at arrangement positions of light sources of a backlight portion. The number of added luminance calculation points is decided by the difference in the emission luminance between adjacent divided regions. On the other hand, the emission luminance distribution of the backlight portion is stored in a memory as data in advance. The luminance of the added luminance calculation points is obtained by superimposition of the emission luminance distribution which is stored in the memory and the emission luminance which is determined for each divided region.
However, in the technology described in Patent Document 1, a large memory capacity is required in order to store the data of the emission luminance distribution of the backlight portion in the memory. Furthermore, since a superimposition calculation is carried out in order to determine the luminance of the added luminance calculation points, the amount of calculation involved becomes extremely large. Therefore, the size of the circuitry and the costs increase. Consequently, there is a requirement to enable the display of images of high quality by accurately estimating the emission luminance distribution of the backlight portion without increasing the size of the circuitry and the costs.    Patent Document 1: Japanese Patent Application Publication No. 2010-079023